Large gable roof. The design of the truss system of a simple gable roof. Assembly and installation of a layered structure

You will be able to build a reliable house if you build for it quality roofing. To do this, choose good project, calculate how many materials will be needed to build one or another part of the house. Fastening your rafters gable roof do it conscientiously.

Do not forget that you will need to make high-quality waterproofing throughout the house and on the roof, insulate your home. Choose the best roofing material you can afford. For each type of roof, the rafters are made in their own way.

You don't have to build as you see fit. There are certain, proven technologies for building houses. Read the instructions, buy the right materials and proceed on your own or with helpers to build your home.

For example, according to the norms, the truss system is considered reliable when it can withstand a pressure of 200 kg per m2. First, decide what kind of roof you will make over the house, and then study the features of installing rafters for it.

In this article

How to give strength to the truss system?

Perfect when you've built country cottage personally. You can choose the design of the house and the layout of the rooms as you like. Personally choose and order quality material and participate in all stages of construction, and then the arrangement of your home. In such a house, where every corner is familiar, it will be pleasant to live.

About rafter legs

A large load falls on the rafters - the weight of the roof. They must be of high quality, reliable and well fastened.

Layered rafters include the following materials:

• lying down;
• Rafter legs;
• Racks;
• Struts.

The legs of the rafter legs are bars of medium thickness. They are installed along the slopes. It is the rafters that keep the roof from deflecting in one place or another. The weight load of the coating is distributed to other parts of the roof.

Structures are made layered when there are too large runs between vertical posts. When you are given a project, the step between the rafters will already be calculated there. The fastening of the rafters on a gable roof should be such that the roof after installation remains strong and lasts a long time. Racks are provided here, which similarly support the roof.

Types of rafters

The rafters are included in the roof frame and can be according to their specifications. sloping and hanging characteristics. Let's take a closer look at each type:

• The layered under 2 heels have supports and they are reliable. The fastening of the rafters to the Mauerlat is such that the lower end rests on the Mauerlat or on the upper crown of the log house located on the ceiling. The lower one can rest on another rafter located in the run. This beam is horizontal and lies under the ridge. In the first case, the truss system is spacer, in the second - non-spacer.
• Hanging rafters with their top rest against one another. And the bottom is located on another beam, which is called a puff. It connects the heels located below from 2 rafter legs. It turns out a triangle, which is called a truss truss. Due to the tightening, there is no strong stretching of the materials. And this means that the load on the walls will only go from top to bottom. This design of rafters is called spacer. Its advantage is that it does not create additional load on the walls of the house.

When you purchase beams for rafters, do not be too lazy to drive to the warehouse. The wood should be seasoned, not wet, even and not chipped, with no signs of mold or bugs. Buy only high-quality material, give up the bad. Then you will treat the bars with an antiseptic composition so that they do not become moldy or insects spoil them.

Fixing the roof beams

The beds serve as a support for the bars and so the run is supported. The legs of the rafter will rest against the Mauerlat with one of the ends, and with the second into the runs. They are attached to the latter.

Struts are made to make the rafter legs even more stable.

Make sure that the connections between the parts are strong and reliable. Fasten the parts to each other:

• tie-in method;
• nails;
• anchor bolts;
• Self-tapping screws are used.

Mounting methods

When you are just starting work on the construction of the roof, you need to attach the Mauerlat around the perimeter of your walls. What it is? big bar, it is attached to the load-bearing walls of the house using anchor bolts. Mauerlat is the basis for a roof with rafters.

Before assembling the truss truss, you must carefully cut all the planks with beams and beams. They are cut at an angle.

At the top, where the base of the Mauerlat, the rafters must be fastened end-to-end using screws. Want to avoid cracks? Drill a hole slightly smaller than the screw itself.

The most popular slings made of wood. They are preferred by the vast majority of those under construction. The material is lightweight but durable. Both an experienced builder and a beginner who decides to build a house on their own will be able to work with him.

We install rafters on a gable roof on our own

Many make such a design when the rafter legs hang down. The system is good for both home and bath. Some work can be done on the ground, and then lift the bonded material to the installation site. There is relatively little lumber for such a structure, which will allow you to save.

1 triangle of rafters is required, which is made according to clear dimensions and adhering to the rules. Made rafters, which will have well-measured and fastened crossbars with puffs, are pulled onto the roof. Here they need to be placed in certain places vertically and very evenly. Attach them to the ridge with Mauerlat.

If the slopes near the roof are longer than 4.5 m, then in order for the system to be stable and more reliable, you need to install racks in a vertical position. One of their ends will support the rafter leg, 2 will rest directly on the beam located on the ceiling.

Do this and it does not matter which rafters you installed: layered or hanging. When slopes are added to the structure, it becomes stiffer. Do not forget that the rafters are most often attached to a ridge beam with a Mauerlat. A reliable gable house will come out.

How to avoid additional payments?

Entrust the creation of a project at home to a professional. He will tell you what diameter in section the beams are needed, the length of the slats and other details. After all, the specialist knows that the rafter system holds the roof. It takes the biggest load and needs correct calculations, high-quality building materials.

It’s better not to ask advice from house builders like yourself. Yes, they built their house, but how strong is it? Not known.

It is best to contact a familiar foreman and ask him good advice. After all, he owns the documentation. There are clear rules permissible load per 1 m2, which must be followed when building a house. The documentation states what kind of load is given and what material will cope with it.

Take a notebook with a pen to a meeting with the foreman and immediately write down his advice. So, you definitely won’t forget anything, you won’t mix it up. Build it the way he expertly recommends.

For gable roofs, most owners make rafters from wood. Choose the one that has matured. Now process it carefully so that the mold does not start, the bug cannot undermine.

When you assemble the structure, make sure that the angle between the rack with the struts is no more than 45 degrees. Wooden beams must be cut obliquely so that the construction truss tilts at an angle of 40 degrees.

Rafter parts can be attached to each other not only with brackets, but also with corners. Purchase right size metal corners to attach rafters to the Mauerlat. The latter in any of the parts must be strong and reliable. Parts of the system can be interconnected with nails with cutouts, corners with screws, and other devices.

When you build a roof, do not fuss. Everything must be done soundly and thoroughly. After all, even wooden frame houses cost at least 50 years, and log cabins and 100.

Your task is to adhere to technology, not to make mistakes anywhere so that the roof does not warp after a year or 5. Consult with craftsmen and experienced comrades who have already made roofs for themselves or to order, and gradually build a roof.

Execution variations roof structure gable roof weight. Its appearance will largely depend on what will be attic space heated or cold, from the presence of load-bearing partitions, the choice of roofing material and, of course, from the taste preferences of the developer. Despite the variety of roof devices ( truss system And roofing cake) the basic installation rules remain unchanged.

The main stages of installation of a gable roof

Gable roof projects

Before starting the installation of the roof, it is necessary to draw external forms of the future frame, indicating its configuration and height, so that in total the gable roof looks proportional to the overall structure, in a word, clearly imagine the structure of the gable roof rafters. This can be done in any way convenient for you, the main thing is to keep the scale for a real vision of perspectives. From experience it can be said that optimal height roofs are considered 1/3 of the value of the length of the house. We immediately embody our ideas regarding a straight or broken slope, branching in the main lines (Fig. 1), residential or non-residential attic space and the type of roof itself, it can be hanging and layered. The latter option is more often used in the construction gable roofs, since it is more practical and economical in terms of lumber consumption.

After deciding on the appearance and functional purpose construction, it is necessary to draw a diagram of the truss system and make its layout in the projection. This is necessary in order to calculate the required amount of material for the construction of the roof.

The expenditure item will largely depend on how complete and rational the calculations will be performed. general budget for roof installation. For example, if you know in advance that you will need N number running meters timber, then when cutting it is necessary to take into account standard length lumber and the size of the rafter leg. As a rule, long structural elements have to be made docking, therefore, without competent cutting, you can get an overestimated percentage of waste.

Despite the fact that gable roofs are considered the most convenient and economical in terms of laying roofing, it will not be superfluous to calculate the amount of sheet or piece material. Since the installation of each of them has its own characteristics, the need for overlap, the number of ridges or waves, technical features (one-sided capillary groove), etc., when calculating total area surface must take into account all these subtleties.

The wave height of the slate and the thickness of the sheet also matter if slate is chosen as the roofing material.

According to GOST 30340-95, 8 wave and 7 wave slates are produced with the following parameters: wave height h - 40 mm, wave pitch (distance between adjacent ridges) - 150 mm, and sheet thickness - 5.2 or 5.8 mm.

Consumables calculation example

IN ideal when the installation of a gable roof is carried out according to the project, a selection of all structural elements is made with the designation of the length and quantity of each item. Using the rational cutting system, the volumes are summarized by:

• Lumber (lm)
• Insulation (m2)
• Vapor barrier membrane (m2)
• Roof covering (quantity in pieces, m2)

For clarity of calculations, we will take as a basis a house with specific dimensions

• Width (a) - 5 m
• Length (in) - 8 m
• Corner at the top () - 1200
• Slope angle (A, C) - 300

We start by calculating the height of the roof, it is calculated as follows

h \u003d ½ x a / tg  / 2 \u003d 0.5 x 5 / 1.73 \u003d 1.44 mm

the length of the rafter (AB), according to the right triangle theorem, will be equal to the product of ½ the width of the house divided by

per sine ½ angle at the apex

L (AB) \u003d 1/2 x a / sin  / 2 \u003d 1/2 x 5 / 0.87 + 0.5 \u003d 2.87 m

Do not forget to add the length to the resulting length eaves overhang, it is determined in the range of 0.5 ÷ 0.8 m. Therefore, the final size of the rafter leg will be 2.87 + 0.5 ÷ 0.8 = 3.37 ÷ 3.87 m (we will stop at the 3.5m option)

S over roofs \u003d a x L (AB) x 2 \u003d 5 x 3.5 x 2 \u003d 35 m2

This is not the final figure for the amount of roofing material that will be needed to cover the roof. To it you will need to add the percentage of waste based on the cutting according to the roof configuration. For each option it will be individual, therefore final result will be known after specific calculations.

Lumber for the crate is also easy to calculate. The step between the purlins (m) is 300 mm. Total

M \u003d L (AB) / m x in \u003d 3.5 / 0.3 x 8 x2 \u003d 187 p.m.

The board for the rafters is calculated in the same way. The step between the rafters is set, it can vary from 600 to 1000 mm, the cross-section of the board, the weight of the roofing pie are taken into account, the multiplicity, which is dictated by the width of the heat-insulating mats and the size of sheets of moisture-resistant plywood or OSB boards, plays an important role when making a continuous crate.

All other elements are calculated according to the above scheme.

Roofing tool kit

After you have fully decided on the structures of the truss system and the roofing pie, you can adjust the classic list of tools that you will need to build the roof. It is very convenient for working at the top to have a belt for tools, so they will always be in one place and at hand. Its kit should include:

• Roulette
• Pencil or marker
• Lace (beat)
• Hammer
• Roofing shears
• Putty knife
• roofing knife
• Construction tape
• Hacksaw
• Screwdriver with a nozzle for self-tapping screws

In some cases, mastic-based adhesives and polyurethane foam may be needed.

Some devices greatly simplify the installation process, these are templates and rails with markings.

Roofing stuff

It is also worth paying attention to the so-called roofing details, which the developer often does not pay attention to, but they also affect the functionality and durability. roofing system. The use of low-quality self-tapping screws (without the manufacturer's brand and with a thickness of EPDM gaskets less than 2 mm) leads to roof leaks. Not durable paintwork on fittings over time can be broken and spoil appearance roofs. Another element that is important when constructing a roof is snow retainers, their absence increases the risk of snow avalanches from the roof. In turn, this can lead to damage drainage system, buildings or cars under the roof. The next problem that worries developers is the problem of condensate, it is associated with insufficient ventilation of the under-roof space. To improve air exchange, it is necessary to provide for the installation of ventilation outlet elements in the roof surface, they allow you to ventilate the under-roof space more intensively, respectively, to avoid the problem of condensate.

They also forget to prescribe antiseptic formulations as an item in the expenditure item, without which it is impossible to imagine modern construction from wood.

Rafter system of a gable roof. Installation and its features.

The beginning of installation begins with the installation of a support beam - Mauerlat. It is installed on load-bearing walls and fastened with pre-built anchor bolts or metal studs. The accuracy of the installation of the entire truss structure depends on how evenly the Mauerlat is mounted. His straightness

checked with a level, if necessary, alignment is done using linings or squeezing protruding parts. The flatness of the support beam allows one template to be used to make all the table legs on the ground, rather than having to fit each in place. It is recommended to perform the rafter support assembly on the Mauerlat using one of the methods indicated in Figure 3.

It is highly undesirable to perform a wash down on a Mauerlat or on a ridge run, this can reduce the bearing capacity of the supporting elements.

If the project provides for a ridge run, and this is more reliable option, the next step is to install the beam at the top of the gables. Mounting points A and B in Fig. 1 are made according to the schemes shown in Fig. 4

The ridge run is made from a board 50x200-250 mm, the ends of the beam are treated with an antiseptic composition and wrapped with a waterproofing material, the end part is left open for air access. Assembling a truss structure with a ridge run is much easier than without it. The fact is that the presence of a longitudinal beam allows you to install a pair of rafters separately, which saves time and labor costs.

Roofing pie device

Upon completion of the installation of the truss system, they proceed to laying the vapor barrier layer. roll material roll out parallel to the ridge run and fasten with inside roofs to rafters. Butt joints are overlapped and sealed with adhesive tape.

From above, the space between the rafters is filled with insulation. To ensure the protection of thermal insulation from moisture due to possible roof leaks or condensate forming on inner surface roofing installation subroofing waterproofing. She is nailed with outer side rafters with nails or staples and fasten with counter rail bars.

Next, a crate is installed, its design is selected depending on the roofing material. A ventilated gap is created with the help of the counter rail and the batten, which ensures the air-dry state of all roof materials.

Roofing is the final stage in the construction of the roof. It is applied according to the manufacturer's instructions. At the end of the main work, they begin to assemble and install drainage systems, ventilation, snow retainers and stairs for Maintenance roofs.

In previous articles that described the roof structure, we already said that the hanging rafters rest on the Mauerlat with their lower end, and the upper ends of adjacent rafters abut (either directly or through a ridge board) against each other. In the most simplified version, this is shown in Fig. 1:

Picture 1

I think it is obvious to everyone that with such an arrangement, there are bursting loads on the walls. To reduce them, puffs are added to the truss truss. But let's talk about everything in order.

As an example, let's take a house with a semi-attic in the Volgograd region. The sum of snow and wind loads is 155 kg/m 2 . The dimensions of the house box are 8x10 meters. The thickness of the walls is 50 cm. The angle of inclination of the slopes is 40 ° (see Fig. 2):

Figure 2

STEP 1: We install . In this design, in addition to the usual loads, bursting forces will act on it, tending to move it off the wall. For more reliable fastening, you can add more metal mounting plates to the anchor bolts (or studs) (see Fig. 3). The plates can be fixed to the wall, for example, with frame anchors, and to the Mauerlat, you can use nails, self-tapping screws, and capercaillie.

Figure 3

STEP 2: We determine the required section of the rafters. We make the calculation in the "Arch" tab (see Fig. 4):

Figure 4

The cross section of the rafters is taken 50x200 mm in increments of 60 cm.

A question may immediately arise here. Where do we get the distance from the ridge to the puff (crossbar). We have it equal to 2 meters. Earlier on the site, we already said that before proceeding with the construction of the roof, we need to make a drawing of it on paper, be sure to scale (in all proportions). If you know how, you can draw on the computer. Further, according to this drawing, we determine all the dimensions and angles of interest to us.

Puffs are installed between hanging rafters to reduce bursting loads on the walls. The lower the puff, the more useful it is. Those. the less bursting load falls on the walls. But since in our example, puffs still play the role ceiling beams attic floor, then we determine the height of their location based on the height of the ceilings we need. I took this height of 2.5 meters (see Fig. 5):

Figure 5

STEP 3: We make a template for the lower rafter cut. To do this, we take a piece of board of the section we need about a meter long, apply it to the Mauerlat at our angle of inclination of the slopes of 40 ° (orient yourself along the pediment) and make the markup, as shown in Figure 6:

Figure 6

The vertical and horizontal lines we need (shown in blue) are drawn using a level. Depth washed down 5 cm.

So let's make a template.

STEP 4: We install a ridge board, through which all the rafters will be interconnected. First you need to outline the place of its installation.

We take the template made earlier and apply it to the Mauerlat. We are interested in the size shown in Figure 7 (here it is 18 cm):

Figure 7

Let's call the lower point on the Mauerlat point "A".

We transfer the resulting size to the top of the pediment, make markings in accordance with Figure 8:

Figure 8

Let's designate the lower right corner as point "B". Now we can measure the distance from the attic floor to point B (the length of the temporary posts).

We install strictly vertically temporary racks from a 50x200 board and put a ridge board of the same section on them. Under the racks for their fixation, you can put a board fixed with simple dowel nails to the floor slabs (see Fig. 9). It is not necessary to fasten strongly, then we will remove it. The distance between the racks is not more than 3 meters.

Figure 9

We fasten the ridge board to the gables with metal brackets. The stability of the racks is provided by jibs.

Perhaps you could see somewhere how hanging rafters are installed without a ridge board (see picture on the left). This method is very familiar to me, we used to do this too.

But when we tried the option with a ridge board, we settled on it. Despite the fact that it takes some time to install the racks and the ridge board, the subsequent installation of the rafters is much more convenient and faster. In the end, you win in time. In addition, the design is more stable and more geometrically even.

STEP 5: We manufacture and install rafters.

We do the rafter like this: take a board desired length, we apply a template to one end, mark it out and make the bottom washed down. Then we measure the distance between points "A" and "B" with a tape measure (see Fig. 7-8). We transfer this size to our workpiece and make the top washed down. The angle we need for the top notch is on our template (see Fig. 10). We have it equal to 90 ° + 40 ° = 130 °

Figure 10

Thus, we put all the rafters (see Fig. 11)

Figure 11

The connection of the rafters with the Mauerlat here does not look the same as it was, for example, I think you have already understood that this is due to the presence of bursting loads, which were not in that version. However, in future articles you will see that this option is just one of the possible, and not the only correct one. We will use more familiar to us washed down. The main thing is to securely fasten the rafters to the Mauerlat.

At the top, the rafters will protrude beyond the ridge board. You can drive small bars between them, or you can leave it as is. This, in principle, does not play any role (see Fig. 12):

Figure 12

We fasten the rafters to the ridge with nails or self-tapping screws. Any additional fasteners is not required here. In general, in this design, thanks to the lower gash, the rafters are obtained, as it were, sandwiched between the Mauerlat and the ridge board.

STEP 6: Installing braces.

We make them from boards of the same section as the rafters. There is no need to make any cuts and cuts here. We make puffs superimposed on the rafters. We fasten them with several nails and tighten them with a threaded stud with a diameter of 12-14 mm (see Fig. 13):

Figure 13

Thus, we install all the puffs and remove our temporary racks on which the ridge board was placed:

Figure 14

Now you can guess the purpose of the small windows in the upper part of the pediment. Through them, ventilation of the insulation will be carried out, which will lie on the ceiling of the half-attic floor (between puffs).

STEP 7: We attach the filly of the cornice overhang to the lower ends of the rafters (see Fig. 15). We make them from boards with a section of 50x100 mm. We make the length of the filly such that we get a cornice overhang of the width we need (40-50 cm), and that it overlaps the rafter by at least 50 cm. We fasten the filly with several nails and tighten with 2 threaded studs. In the middle part, for additional emphasis on the wall, you can fasten a small bar to the filly with nails or self-tapping screws.

Figure 15

Please note that at the junction of the filly of the overhang with the Mauerlat, we do not drink on it, because. this will reduce it and without that not a large cross section. Here we first make a small cut in the Mauerlat itself (see Fig. 16):

Figure 16

To make the cornice even, use a lace. First put the extreme fillies, then pull the lace between them and put all the rest. In Figure 17 the shoelace is shown in blue.

Figure 17

Step 8: The following steps are already known to us from previous articles. We put the fillies on the pediment and fasten the wind boards (see Fig. 18):

Figure 18

STEP 9: Now we can leave the cornices in the form in which they are.

Let's see another version of the eaves overhangs (see Fig. 19):

Figure 19

Such "earrings" are made from inch boards 10-15 cm wide. We fasten them with self-tapping screws.

Thus, now it remains for us to hem the siding belts to the bottom of the cornices; fastened to the rafters protective film, make a counter-lattice and crate; cover the roof roofing material. We have covered these steps in previous articles. I think it makes no sense to repeat here and when considering other roof structures in the future.

The truss system of a gable roof is a simple design that is available for a do-it-yourself device even for a novice developer. It is only necessary to make preliminary calculations, familiarize yourself with the details and stages of the construction of the roof, and calculate the materials needed for installation. When calculating, it should be taken into account that load bearing capacity gable roof depends on the influence on it of loads from wind, snow, weight of materials.

In order to make the process of building a gable roof truss system as easy as possible for you, below is a detailed step-by-step instruction for the installation of the truss system with their own hands.

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Requirements for building materials

For the device of the truss system the best option will use lumber from conifers wood - pine, spruce or larch, I - III grade.

The material for the rafters is taken not lower than grade II, the Mauerlat is made from boards or timber of grade II, for racks and girders material of grade II is taken, the lathing is made from grade II-III lumber, it depends on the roof. Crossbars, puffs are made of Grade I material. On linings, linings, material of grade III can be used.

Note! Lumber must be dry with a moisture content of not more than 20%. It must be processed before installation. flame retardants and antiseptics against fungal diseases.

You need to store lumber under a canopy, providing protection from the sun and moisture. Level the storage area, shift the lumber with linings for ventilation.

For installation, fasteners are required: couplers, plates, studs, bolts with washers and nuts, self-tapping screws with EPDM gaskets, 2.8 mm thick, mounting tape, galvanized brackets.

Brackets are used when fastening the Mauerlat, they are fastened with nails or self-tapping screws.

KR corners serve to attach the rafters to the Mauerlat, prevent the rafters from moving.

Whole fixing material must be made of high quality material and have corrosion protection.

Tools for the construction of the truss system

To install the gable roof truss system, you will need the following set of tools:

• tape measure, different lengths 5, 10, 20 meters;
• markers, pencils;
• cord, for stretching;
• hammers, different purposes, nail puller;
• scissors, for cutting;
• roofing knife;
• putty knife;
• scotch;
• hacksaws, electric saw, electric drill with various drills and nozzles;
• screwdriver with nozzles;
• markings, horizontal and vertical levels;
• rails, rulers;
• mounting foam;
• safety belt and rope - for safe work.

Keep all roofing tools in a tool bag for safety.

Types of truss systems for a gable roof

sent rafters

Rely on Mauerlat and racks mounted on inner wall, with a step equal to the rafters. To give rigidity during spans of 6 m, struts are additionally placed.

The scheme of the rafters of a gable roof

hanging rafters

If the building is small in width, it is possible to arrange a truss system when the rafters rest on the mauerlat or walls, without intermediate supports. The maximum span is 9 meters. Such roofs can sometimes be arranged without a Mauerlat. The rafters are installed on the wall, using gaskets, on the rafters in this embodiment, a bending moment acts.

To unload, put wooden or metal lining. They securely reinforce the corner. For hanging rafters longer span headstock and struts are installed. For hanging systems, the rafters are arranged with a larger section, and the lumber is chosen not lower than grade I II.

Scheme of hanging rafters of a gable roof

Calculation of the truss system

It is possible to determine the cross-section of a gable roof beam in the truss system by collecting all the loads acting on it: the weight of the coating, lathing, snow, wind pressure, precipitation.

Permanent loads can be determined by the weight of 1 m 2 of roofing, battens. It is important that the weight per 1 m 2 of the roof is in the range of 40-45 kg.

Variable loads from snow, wind are calculated from tabular values normative documents SNiP, depending on the height of the building, temperature zone. The load from snow is equal to its weight multiplied by a coefficient depending on the slope of the slope. All these calculations are carried out during the project.

And if there is no project, and the roof is being erected on a small building? You need to look at the construction of a house in the neighborhood, which is being carried out according to the project, the roof area is the same as your building. The gable roof truss system will serve as a model.

Rafter beam dimensions

At the top point, a ridge is laid that connects the rafters. The height of the ridge depends on the slope of the roof. The slope is influenced by the choice of coating material. Minimum dimensions are:

• For tiled roofs, slate 22 gr.;
• for metal tiles - 14 gr.;
• ondulin - 6 gr.;
• corrugated board - 12 gr.

The optimal angle is 35-45 gr. slope, provides a quick discharge of water and snow. In regions with strong winds, roofs are made flat and then the angle of inclination is within 20-45 degrees.

You can determine the height by the formula: H \u003d 1 / 2 Lpr * tgA. Where A is the angle of inclination, L is the width of the building.

The task is simplified when using a ready-made table. The coefficient depends on the width of the building and the angle of inclination. Multiply the coefficient by 1⁄2 of the width of the building.

The rafters are made from pine or spruce bars, with a section of 50 × 100 mm, 50 * 150 mm.

The size of the rafters depends on the pitch. The pitch of the rafters is smaller, a larger number is installed, the cross section will decrease. The distance between the rafters at a gable roof is in the range from 600 mm to 1800 mm, it all depends on the design of the roof and the materials used for its construction.

The roof does not end at the level of the walls, it is extended 500 mm outwards. The rafter leg can protrude, or a board or bar is built up. In this case, moisture does not fall on the wall, the foundation is not poured.

Step-by-step installation of the design of the gable roof truss system

The gable roof truss system consists of the following elements:

1. Mauerlat.
2. Lie down.
3. Racks.
4. Rafter.
5. Struts.
6. Puffs.
7. Crate.

Mauerlat installation

Mauerlat fasteners to a monolithic reinforced concrete belt

Mauerlat evenly distributes the load on the walls of the building, its installation can be done in several ways:

• fasten to the wall through a reinforced concrete belt with studs;
• studs are inserted into the masonry;
• simple and common way to simple roofs, fastening with wire rod.

For him, take a bar with a section of 100 × 100 mm, 150 × 150 mm or 200 × 200 mm. Which section to choose depends on the size of the roof and its coverage. The Mauerlat is joined along the length, for this, make a 100 mm cut, 500 mm long, fold the bars and fasten with studs.

In the corners, the Mauerlat is tied with cuts to the floor of the beam, fastened with brackets or bolts. At wooden buildings, Mauerlat is the last crown. On brick walls, perform a monolithic reinforced reinforced concrete belt, with a section of 400 × 300 mm. Align the pins with a thread of 12 mm in diameter along the belt, through 120 mm, for fastening.

Drill holes with a diameter of 12 mm in the Mauerlat, lay them so that the pins go into the holes. Tighten with nuts from above. Previously, we lay two layers of roofing material or roofing felt under the bar. On the outside of the wall, lay the Mauerlat with bricks. Laying the Mauerlat on a horizontally and vertically even base. It is necessary to check the horizontal level of the surface. Check diagonals. Align with pads if necessary.

Installation instructions for beds, racks, rafters, struts and puffs

Do-it-yourself do-it-yourself installation of a gable roof truss system is carried out in the following order:

1. To carry out the installation of the bed, with the sent rafters.
2. Mark the installation step of the rafter legs.
3. Prepare according to the size of the rack.
4. Install them, if necessary, unfasten them with spacers.
5. Lay a run. Check geometry. Install fastener.
6. Try on the first rafter leg, mark the cutting points.
7. Mark the points and install the rafters at the beginning and end of the roof, pull a cord between them in order to align the rest of the elements with it.
8. Having installed the rafter leg, we attach it first to the Mauerlat, then to the ridge run, to each other.
9. Screw every second leg with wire to the Mauerlat.

The fastening of the rafters to the Mauerlat is done with the help of notches, thrust corners and a hemmed support bar. Reinforce with nails or staples.

Methods for attaching rafters to the Mauerlat

Install the support posts on the beds or linings and linings. A bed is a beam 50 × 100 mm or 50 × 150 mm, laid on the middle wall along a roofing felt lining. Put under the lining brick posts, 2 bricks high.

The rafter legs are connected to each other on the ridge. Consider the common connection nodes of the truss system:

1. They make cuts at one leg and washed down at the other. Insert one leg into the cut of the other and fasten with a bolt.
2. Install overlays, wooden or metal.
3. With the help of cuts in the run, they are fixed with nails or bolts.

Methods for connecting rafters on a ridge

For the stability of the roof to wind loads, puffs, struts and runs are installed. The tightening is a bar 100 × 150 mm, runs and struts are made from a bar 50 × 150 mm or 100 × 150 mm.

With the installation of contractions, the reliability of the rafter design increases. The sections of the beam are the same as the rafters. They are attached to the legs with bolts or nails. The bracing device adds rigidity to the structure. They are installed tightly, to the surface of the rafters.

Lumber has a standard length of 6 m. Rafters can be longer. Then you need to connect them. There are several connection methods:

1. Fasten by applying bars on both sides at the junction, connect them with nails in a checkerboard pattern.
2. Overlap, one part of the rafter to another, at a distance of 1 meter, fasten with nails in a variable order.
3. Run a cut obliquely, cut out part of the legs of the rafters, connect them, reinforcing them with bolts.

Lathing device

A crate is laid along the roof rafters. It serves to distribute the load from the roofing material, snow on the rafters. Acting air gap between the roof and truss system.

The design of the crate depends on the accepted roofing material:

• under soft tiles make the crate solid, an anti-condensate film is laid on the rafters, pressed against the top with a counter rail, the crate is nailed onto it, then the OSB boards and lining carpet, lay tiles on top.
• under the roof of the corrugated board, the crate should be sparse. The step of the lathing depends on the brand of corrugated board, its thickness and the angle of the roof.
• crate under standard slate do with a step of 500 mm from a bar 75 × 75 mm or 50 × 50, as well as boards from 30 × 100 mm. It is necessary to take into account the design features of the roof, with the final choice of a suitable option.

The lumber from which the crate is made is pine of the first or second grade. It is advisable to take a width of no more than 14 cm. With a width of more, the boards can warp and damage roof deck. The length of the nails should be three times the thickness of the crate. Lay the boards along the ridge. Set the first board of greater thickness to the height of the roofing.

To arrange a continuous crate along the slope of the roof.

With the first layer, lay a board along the ridge from it at a distance of 500-1000 mm next, and so on. With the second layer, lay the crate in the direction along the rafters. Arrange the joint between the boards only on the rafters in a run. The nail is sunk completely with the head into the pulp of the wood.

Cornice overhangs

Arranged to protect against precipitation, play an aesthetic role. Eaves overhangs suit tightly without gaps. The final stage in the construction of the roof.

Scheme of the device of the eaves overhang of a gable roof

Gable

The gable roof has two gables. They have the shape of a triangle, with the apex at the ridge and the sides coincide with the slopes of the roof. Gables support the rafters and enclose the attic space. Protect from wind and precipitation, give stability to the roof.

IN wooden buildings the pediment is made frame. IN brick buildings, frame or brick. Gables made of brick or gas block are erected before the roofing device. They require very precise execution.

Frame gables fit into the finished opening when the truss system is already assembled.

The frame is made of bars or boards. The frame elements are connected on spikes or to the floor of a tree, all fastened with nails. They are sheathed by nailing boards, lining or siding, maintaining the color in the decoration of the facade of the building. For the device of a window opening, an additional frame is made under it according to the size of the window. If the attic is insulated, then the pediment also needs to be insulated. Insulation is laid in the middle of the frame. A mineral wool insulation with reduced flammability is used. From the outside, the frame is upholstered with a hydro-windproof film or windproof membrane, from the inside under finishing material nail the vapor barrier film or vapor barrier membrane.

In contact with

The gable truss system is chosen by many owners of residential buildings. This is due to its high practicality and ease of creation. If you carefully study the structure of the gable roof truss system, then the process of its formation can be done by hand. The resulting design is highly reliable and durable, and also guarantees excellent protection of the building from cold and precipitation.

Main elements of the system

The design of the gable roof truss system is considered simple. It consists of a variety of elements made from wooden elements having different length, configuration and section. The main nodes include:

• Mauerlat. Represented by a beam with a section in the form of a square. To create it, coniferous wood is usually used. Its dimensions vary from 10 to 15 cm. It is laid along all the load-bearing walls of the building. It is fixed to them with the help of anchors or special rods. If you make and attach it correctly, then it will evenly distribute the load from the rafter legs along all the walls of the structure.
• Rafter legs. They are created from a bar with dimensions of 15x10 or 15x5 cm in section. With their proper connection, a roof contour is formed that has the shape of a triangle. It must be strong and reliable in order to withstand heavy loads from rain and wind. Rafter legs must be fixed at a distance of about 1 m from each other.
• Sill. Made from square wooden beam, whose cross section is equal to . It is laid horizontally on a load-bearing wall inside the building. Due to it, the load coming from the roof racks is evenly distributed.
• Puff. This element applies if hanging structure. It is installed on top of the resulting triangle of rafter legs, which ensures its stability.
• Racks. To create them, a square beam is used. They are in a vertical position. They bear the load from the ridge, after which it is transferred to the load-bearing wall inside the building.
  
• Struts. The installation of these elements is necessary in order to obtain a special transmission element located between the rafter legs and various load-bearing parts. Due to their reliable connection with a tightening, the creation of a strong structure is guaranteed.
• Crate. It is assembled from bars or boards. Installed perpendicular to the legs of the rafters. It provides the transfer of gravity from the roof of the roof to the legs of the rafters. It is advisable to use to create this element edged boards. If you plan to create a coating on the roof of soft roofing materials, for example, shingles, then the crate must be continuous.
• Skate. It is represented by the topmost element of the entire roof. Due to it, its two slopes are connected. Its assembly is carried out by connecting the legs of the rafters at the top of the roof. It must be placed in a horizontal position.
• Eaves. It protrudes from each wall of the building by about 40 cm. Its installation is due to the need to protect the walls from water flows as a result of precipitation.
• Filly. Provides the ability to create a roof overhang. They are used exclusively in a situation where short rafter legs are used, so they are lengthened by fillies.

Important! The step between the legs of the rafters is chosen in accordance with the severity of the roof, since the more weighty it is, the smaller this gap should be.

Thus, the installation of a gable roof truss system is considered quite simple, so it is not difficult to make this design with your own hands.

Types of structures

The rules and features of the installation of this design depend on the selected variety.

Types of gable roof truss system:




All options have their own characteristics, so their characteristics are preliminarily evaluated. If you plan to install a gable roof truss system with your own hands, then a simple symmetrical design is chosen.

Important! The basis for obtaining the ideal result is competent calculations, and if they are incorrect, the roof will not be reliable and durable, and it will also be dangerous to live in such a house.

How to choose the material to create the system?

When choosing a material, the following rules are taken into account:

• rafters are created exclusively from high-quality wood, on which there are no rotten areas, damage, knots or other shortcomings;
• edged boards are purchased to form the crate;
• all wood should be well treated with antiseptics and fire retardants.

Important! Knots are allowed, but their length cannot be more than 1/3 of the thickness of the timber used.


Calculation rules

To make the gable roof truss system reliable and of high quality, a lot of attention is paid to competent calculations. They should affect all elements of the future design:

• Load calculation. Any system is affected by two types of load. The constants will regularly act on the structure, and this includes the weight from the roofing of the roof, battens, thermal insulation material, waterproofing, extensions and finishing materials used for the attic. Typically, this load is 40 kg / m. sq. Variable loads may have different strength, as these include wind, snow exposure, and precipitation intensity. To calculate the load is multiplied wind load specific region by a special correction factor.
• Determining the angle of inclination. A roof with two slopes can have a different angle of inclination, and it is determined by the roofing material used. If mounted soft roof, then for it a slope is selected in the range from 5 to 20 degrees, or metal tiles vary from 20 to 45 degrees.
• Calculation snow load. In winter, the roof can accumulate a large number of snow. In order to avoid any problems with the structure, the frame must withstand these loads. The calculation requires the weight of the snow to be multiplied by the correction factor.
• Definition . The gap between these elements is usually chosen in the range from 60 to 100 cm, and the final choice depends on the roof and the weight of the roof.
• Definition . To do this, it is recommended to use the standard Pythagorean theorem.
• Determination of the section of the rafters. This setting is affected by several important factors: roof loads, type of materials used, length of rafter legs, as well as a step between them.

Important! When calculating loads, the possibility of a storm or tornado is additionally taken into account, since if the house is located in a region where such loads can appear, then a margin of safety is made for the roof, read more:.


Types of rafters

Before direct work on creating a gable roof with your own hands, you should make a special plan, which will contain a drawing and layout of the entire structure. This takes into account which rafters will be used, since the following types can be used:

• . Suitable for small buildings. Their installation consists in fixing the legs to the bearing wall of the structure, as well as to the ridge run. A feature of the use of these elements is that a bursting force acts on the rafter legs, and puffs are used to reduce this effect. They can be made from wood or metal.
• Layered. Suitable for roofs of any shape and size. The layered design is used in conjunction with racks and lying down. The bed is laid parallel to the fixed Mauerlat, so a certain part of the load is transferred to it. This allows you to tilt the legs of the rafters, which are additionally supported by the rack, to each other.
• Combined. They are used when using unusual gable roof configurations.

After determining the main design parameters, the calculation begins the right amount material. Then you can proceed to the direct creation of the truss system.


Assembly of the structure

The do-it-yourself truss system of a gable roof is created only after the preliminary formation of drawings and plans. The scheme of future contraction should be clear and correctly calculated. For this, it is recommended to use special computer programs.

Important! In the presence of Money allowed to contact specialized construction companies for the correct calculation.

Installation of a gable roof truss system is divided into successive stages:

• to the walls of the building. Its installation is carried out along their entire length. If the house is made of logs, then the Mauerlat acts as its upper crown. If the building is selected cellular concrete or brick, then it is mounted on top bearing wall along its entire length. It is required to splice the Mauerlat, for which the bars are sawn at a right angle and connected with bolts. It can be fastened with an offset to the side of the wall or in its center. Laying is carried out on a waterproofing layer, for which roofing material is usually used.
  
• Creation roof trusses. To do this, it is allowed to install bars on the roof or form a structure on the ground, after which it rises to the roof. The second option is often chosen, since it is difficult to perform work on the roof of the house. But to raise the structure made, you will have to use special equipment. Before connecting the legs of the rafters, the correctness of their size and location is checked.
  
• . The formed pairs rise to the roof, after which they are laid on the Mauerlat. For the competent performance of the work, special cuts are made from the bottom of the legs. The process begins with the ends of the roof, located opposite to each other. To obtain a perfect result, temporary fasteners are used when installing the elements. A rope is pulled between the fixed pairs, making the installation of subsequent elements simplified. All rafter legs are mounted, and the correct step between them is checked. Next, a special skate support is installed. All additional elements used in the rafter system are fixed by cutting and brackets. It is allowed to lengthen the rafter legs if necessary.
  
• Skate installation. It is created with the help of a competent connection on top of all rafter legs. Different methods are used for its formation, and it is allowed to use a support bar for this or you can work without it. If a beam is used, then it is allowed to put a skate on it or use the cutting method.
  
• The rafter system is considered to be done, but in order for it to be strong and reliable, it is necessary to thoroughly fix all the elements, therefore, all temporary fasteners are eliminated, in place of which they are applied quality products to fix all parts of the system.
• Lathing installation. This design is intended for easy movement on the roof, and also serves as the basis for laying the roof. Its type and parameters depend on the chosen roof. A solid crate is created if a soft roof is selected. has a distance between the boards within 35 cm. For or slate, this parameter is 44 cm.